Heat dissipation, driving power, and light sources are the most critical parts of a good LED lighting product. Although the heat dissipation is particularly important, the heat dissipation effect directly affects the life quality of the lighting products, but the light source is the core part of the entire product. The stability of the life and output current and voltage of the power supply itself have a great impact on the overall life quality of the product. The LED driver power supply is also a supporting product. At present, the quality of the power supply on the market is uneven. The following provides some related knowledge of LED driver power. 1. What is the LED drive power supply LED drive power supply converts the power supply to a specific voltage current to drive the LED light -emitting voltage converter. Usually: the input of LED drive power includes high -voltage frequency AC (that is, city power), low voltage DC DC , High -voltage DC, low -voltage and high -frequency AC (such as the output of electronic transformers), etc. The output of the LED drive power supply is mostly the constant current source that can change the voltage with the changes in the value reduction of the LED forward voltage. The core components of LED power supply include switch controller, induction, switch component (MOSFET), feedback resistance, input filter device, output filter device, etc. According to the requirements of different occasions, there must be input overvoltage protection circuits, input -lack pressure protection circuits, LED opening road protection, overcurrent protection and other circuits. 2. Features of LED drive power supply (1) High reliability is especially like the driver power of LED street lights, which is installed at high altitude, it is not convenient for maintenance, and the cost of maintenance is also large. (2) High -efficiency LED is an energy -saving product, and the efficiency of driving power is high. It is very important for the heat dissipation of the power supply in the lamp. The efficiency of the power supply is high, its loss of weight is small, and the heat in the lamp will be small, which will reduce the temperature rise of the lamp. It is beneficial to delaying the light failure of LED. (3) High -power factors and power factors are the requirements of the load of the grid of the grid. Generally, electrical appliances below 70 watts, there are no mandatory indicators. Although a single power factors with low power, low power factors have little impact on the power grid, the use of lighting at night, the same type of load is too concentrated, will cause more serious pollution to the power grid. For the LED driver power of 30 watts 40 watts, it is said that in the near future, there may be certain indicators for power factors. (4) There are two types of driving methods now: one is a constant voltage source for multiple constant stream sources, and each constant current source supply to each LED separately. In this way, the combination is flexible, the LED failure all the way, does not affect the work of other LEDs, but the cost will be slightly higher. The other is directly constant current power supply, which is also“Zhongke Huibao“The driving method adopted, the LED is connected or parallel. Its advantage is that the cost is lower, but the flexibility is poor, and it is necessary to solve the problem of a certain LED failure, which does not affect the operation of other LED operations. These two forms coexist for a period of time. Multi -Lu Hengliu output power supply methods will be better in terms of cost and performance. Maybe it is the mainstream direction in the future. (5) The ability to protect the LED protection of LEDs is relatively poor, especially the anti -reverse voltage capacity. Strengthening protection in this area is also important. Some LED lights are installed outdoors, such as LED street lights. Due to the opening of the power grid load and the induction of lightning strikes, the grid system will invade various waves, and some waves will cause LED damage. So analysis“Zhongke Huibao“The driver power should be lacking in the protection of wave surge. As for the frequent replacement of the power and lamps, the LED drive power supply must have the ability to suppress the surge and protect the ability of the LED to not be damaged. (6) In addition to the conventional protection function, the protection function power is best to add LED temperature negative feedback to the constant current output to prevent the LED temperature from being too high;. 3. Classification according to the driving method (1) The current output of the constant current constant current drive circuit is constant, while the output DC voltage changes within a certain range with the size of the load resistance, the load resistance value is small, the output voltage is If it is low, the larger the load resistance value, the higher the output voltage; the constant current circuit is not afraid of the load short circuit, but the load is strictly prohibited; the Hengliu driving circuit is more ideal, but the price is relatively high; pay attention to it; pay attention The maximum tolerance and voltage value used, it limits the number of LEDs. (2) After the various parameters in the stabilization circuit are determined, the output voltage is fixed, and the output current changes with the increase and decrease of the load; Short circuit; drive the LED to drive the voltage -driven circuit, each string needs to add the appropriate resistance to make each string of LED display average brightness; the brightness will be affected by the voltage changes from rectification. 4. The advantages and disadvantages of the overall constant current and the way to follow the way are compared with the overall constant current. Although there are many disadvantages and high costs, the cost is relatively high. But it can truly protect the life of LED and extend the LED, so the constant flow of the road is the future trend. 5. The lack of LED power supply LED -driven power supply is currently inadequate: 1. The technicians of companies producing LED lighting and related products do not know enough about the switching power supply. And not to consider electromagnetic compatibility enough, there are still some hidden dangers; 2. Most of the LED power supply manufacturers are transformed from ordinary switching power supplies to do LED power supply. The characteristics and understanding of LED are not enough; There are almost no standards, most of which are the standard for referring to the switch power supply and electronic rectifier; most LED power supply is not uniform, so most of the amount is relatively small. If the purchase volume is small, the price is high, and the supplier of the component is not very cooperative; 4. The stability of the LED power supply: the wide voltage input, high temperature and low temperature work, over temperature, overvoltage protection and other issues have not solved them one by one. The first is the overall life of the driving circuit, especially the key devices such as: the life of capacitors at high temperature directly affects the life of the power supply; that the LED drive should challenge higher conversion efficiency, especially when driving high -power LEDs, because because it is driven by high -power LED, because because it is driven by high -power LED, because because the driver's high -power LED is because of the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is the driver's high -power LED, because because it is because the driver's high -power LED is because it is even more true, because it is even more so. All the power that is not out of light is used as heat dissipation, and the power conversion efficiency is too low, which affects the performance of LED energy -saving effects. At present, in applications with small power (1-5W), the proportion of the cost of Hengliu driving power supply has been close to 1/3, which is close to the cost of light sources, which affects market promotion to a certain extent.